A device and method for reducing hydrogen content in oxygen by using multi-stage gas-liquid separation technology

Abstract

The application relates to the technical field of gas-liquid separation, and provides a device and a method for reducing hydrogen content in oxygen by using a multistage gas-liquid separation technology, which comprises a separator, the inner cavity of the separator is sequentially divided into a first separation cavity and a second separation cavity from top to bottom, and the first separation cavity is communicated with the second separation cavity; a gas-liquid cyclone inner part is arranged in the first separation cavity; a strong centrifugal force field generated by the gas-liquid cyclone inner part is used for making micron-sized bubbles in a hydrogen-electrolyte mixture coalesce and separate, and free-state fine bubbles in the hydrogen-electrolyte mixture are efficiently removed; a throttling device is arranged between the first separation cavity and the second separation cavity, over-saturated dissolved hydrogen in hydrogen-rich electrolyte after first separation in the first separation cavity is depressurized through the throttling device, the hydrogen is actively precipitated by using static pressure drop, and separation is completed in the second cavity, so that the purpose of reducing hydrogen content in oxygen is achieved. The two-stage progressive separation structure significantly improves the hydrogen separation efficiency, and reduces the hydrogen content in oxygen to a low level.

Description

Technical Field

[0001] This invention relates to the technical field of gas-liquid separation, and in particular to an apparatus and method for reducing the hydrogen content in oxygen using multi-stage gas-liquid separation technology. It is especially suitable for scenarios where the purity of hydrogen and oxygen is required to be high in alkaline, PEM, and AEM water electrolysis hydrogen production processes. Background Technology

[0002] Electrolysis of water to produce hydrogen, as a green and efficient hydrogen energy production technology, has developed rapidly in recent years under the impetus of the "dual carbon" strategy. However, in actual operation, a certain amount of hydrogen often mixes into the oxygen produced at the anode (i.e., hydrogen crossover into oxygen, HTO). This not only causes the loss of hydrogen products, but more seriously, when the HTO concentration exceeds 4% (volume fraction), it will form an explosive mixture, posing a significant safety hazard.

[0003] HTO (hydrogen oxidative stress) is primarily attributed to the physical diffusion of hydrogen molecules through membranes or sealed structures. To reduce HTO, existing technologies mainly focus on improving membrane density, optimizing electrode structures, or adding gas-liquid separation devices such as wire mesh demisters at the gas phase outlet. However, these methods are largely ineffective against HTO caused by liquid-phase carriers.

[0004] Research reveals that the sources of HTO are far more complex than traditionally understood, with dissolved hydrogen and its accompanying liquid phase flow being the key mechanisms leading to excessive HTO levels. By constructing a separate electrolyte circulation loop, the existence and dominant role of "transmembrane liquid convection" were quantitatively confirmed for the first time. The study shows that during electrolysis, because the hydrogen production at the cathode is twice that at the anode, a continuous liquid permeation flow from the hydrogen chamber to the oxygen chamber forms on both sides of the membrane, accounting for approximately 10%–15% of the total hydrogen-side circulation. The dissolved hydrogen concentration carried by this permeation flow is as high as 1.36 times the saturation value, directly leading to a significant increase in HTO.

[0005] The impact of the widely adopted "mixed electrolyte circulation" mode in industry on HTO. In this mode, the electrolytes from the cathode and anode are mixed after gas-liquid separation and then reinjected into the electrolyzer. This results in the cathode electrolyte, rich in dissolved hydrogen, directly entering the anode chamber, causing severe secondary cross-contamination. Comparative experiments show that, compared to separate circulation, mixed circulation can increase the HTO value by up to 84.5%.

[0006] Whether it's transmembrane convection or mixed circulation, the essence is that the electrolyte containing dissolved hydrogen acts as a "liquid-phase carrier" for hydrogen, transporting hydrogen from the cathode to the anode side. Therefore, relying solely on traditional gas-phase end treatments (such as wire mesh defoaming) cannot fundamentally solve the HTO problem.

[0007] However, existing technologies generally suffer from a critical flaw: the separation of gas-liquid separation and dissolved hydrogen removal functions are disconnected. Traditional processes typically separate the separation of entrained liquid droplets in the gas phase from the removal of dissolved hydrogen into two independent unit operations, requiring separate primary gas-liquid separators and subsequent hydrogen removal units. This segmented processing architecture has significant drawbacks: 1. Low system integration and equipment redundancy: The series connection of multiple equipment levels results in a large overall footprint and complex piping, which significantly increases the initial investment and operation and maintenance costs; 2. High risk of leakage: The various units need to be connected by a large number of connecting parts such as flanges and valves, which not only increases the probability of seal failure, but also constitutes a potential safety vulnerability in high-pressure hydrogen-containing environments; 3. Insufficient separation efficiency: Conventional gas-liquid separators have limited efficiency in capturing microbubbles and electrolyte mist, making it difficult to effectively block the entrainment of free hydrogen. At the same time, if dissolved hydrogen is not simultaneously released and removed during the separation process, it will still flow back to the anode side with the electrolyte, accumulating in local areas and causing the hydrogen concentration in oxygen to approach or even reach the lower explosive limit (LEL) of 4%, posing a serious safety hazard.

[0008] Currently, conventional cyclone separators are mostly single-stage structures, making it difficult to achieve both initial separation and deep purification; while separate throttling or degassing units lack compact integration with the main process.

[0009] Therefore, there is an urgent need to develop a compact, integrated gas-liquid separation device capable of simultaneously and efficiently capturing micron-sized bubbles and droplets within a single unit; and actively releasing and separating dissolved hydrogen. This would reduce the path of hydrogen migration from the liquid carrier to the anode at the source, fundamentally reducing the hydrogen content in oxygen and ensuring the inherent safety and operational reliability of large-scale water electrolysis hydrogen production systems. This technological solution has become a core challenge that urgently needs to be overcome in the field of green hydrogen equipment. Summary of the Invention

[0010] The purpose of this invention is to provide an integrated, high-efficiency multi-stage cyclone gas-liquid separation device and method to solve the problem of hydrogen content (HTO) in oxygen in existing alkaline or PEM water electrolysis hydrogen production systems.

[0011] To achieve the above objectives, the present invention provides an apparatus for reducing the hydrogen content in oxygen using multi-stage gas-liquid separation technology, comprising a separator, wherein the inner cavity of the separator is divided into a primary separation chamber and a secondary separation chamber from top to bottom, and the primary separation chamber and the secondary separation chamber are connected. The primary separation chamber is equipped with a gas-liquid cyclone internal device. The strong centrifugal force field generated by the gas-liquid cyclone internal device causes the micron-sized bubbles in the hydrogen-electrolyte mixture to coalesce and separate, efficiently removing free microbubbles from the hydrogen-electrolyte mixture. A throttling device is provided between the primary separation chamber and the secondary separation chamber. The hydrogen-rich electrolyte after primary separation in the primary separation chamber is depressurized by the throttling device. The sudden drop in static pressure causes the supersaturated dissolved hydrogen to actively precipitate out and be separated in the secondary chamber, thereby reducing the hydrogen content in the oxygen.

[0012] Preferably, the separator has a cylindrical structure made of stainless steel or titanium alloy, with a smooth inner wall and no dead corners, and is suitable for long-term stable operation in high-purity, high-humidity hydrogen-oxygen environments.

[0013] Furthermore, the top of the separator is provided with a first gas phase outlet, which is connected to the primary separation chamber, and the bottom of the separator is provided with a liquid phase outlet, which is connected to the bottom collection area of ​​the secondary separation chamber. The separator has a hydrogen-electrolyte mixture inlet on its side wall, which is connected to the inlet on the side of the gas-liquid cyclone internal component. The separator is also provided with a second gas phase outlet on its side wall, which is connected to the secondary separation chamber.

[0014] Preferably, the first gas phase outlet and the second gas phase outlet are independently connected to external pipelines, so that the gas phase discharged from the primary separation chamber and the hydrogen gas evolved from the secondary separation chamber are isolated from each other during the discharge process, avoiding cross-mixing of gases in different pressure zones.

[0015] Furthermore, the second gas phase outlet is located in the upper middle part of the secondary separation chamber to ensure that the discharged gas phase is far away from the liquid phase accumulation area and reduce electrolyte mist entrainment.

[0016] Furthermore, both the first gas phase outlet and the inner wall of the second gas phase outlet are equipped with wire mesh demisters. The wire mesh demisters can be metal wire mesh demisters or corrugated wire mesh demisters, and can be made of materials such as stainless steel, titanium, and nickel alloy. The wire mesh count is 80 mesh, which can effectively remove droplets larger than 3-5μm, with a separation efficiency of up to 99% or more.

[0017] Furthermore, the gas-liquid swirl internal component is one of the following: a swirl tube type internal component, an axial swirl blade type internal component, a corrugated swirl plate type internal component, or a spiral flow channel type internal component.

[0018] Furthermore, the throttling device includes a spiral guide throttling device, which includes a throttling device body, a liquid inlet pipe, and an adjustable multi-hole nozzle. The throttling device body is provided with a spiral guide cavity, which is connected to the liquid inlet pipe and forms a spiral flow channel inside, which is used to generate swirling flow of fluid and achieve preliminary pressure reduction and throttling. The liquid collection inlet pipe has a symmetrical bifurcated structure. The liquid collection inlet pipe is connected to the inner walls of both sides of the separator. The liquid collection inlet pipe is connected to the inlet end of the spiral guide cavity, so as to collect the fluid and introduce it into the spiral guide cavity. The spiral guide cavity is equipped with a rotatable spiral valve core. By rotating the spiral valve core, the flow area of ​​the spiral flow channel is changed, thereby adjusting the throttling opening. The adjustable multi-hole nozzle is connected to the outlet end of the spiral guide cavity. The adjustable multi-hole nozzle includes at least one nozzle with a replaceable orifice diameter, which is used to control the flow rate and throttling opening by changing the nozzle flow area.

[0019] Preferably, the throttling device may be selected from any one of an adjustable throttling valve, a flow-limiting orifice plate, a venturi tube, a capillary tube, a porous medium throttling device, a fixed throttling valve, or a nozzle.

[0020] Furthermore, a pressure sensor and a flow sensor are provided at the inlet of the hydrogen-electrolyte mixture.

[0021] Another aspect of the present invention provides a method for reducing the hydrogen content in oxygen using multi-stage gas-liquid separation technology, the method comprising: S1: First-stage cyclone separation: A hydrogen-electrolyte mixture is introduced into the gas-liquid cyclone internals of the first-stage separation chamber through the hydrogen-electrolyte mixture inlet. The hydrogen-electrolyte mixture enters the gas-liquid cyclone internals through the side inlet and completes the gas-liquid separation process within the cyclone chamber. Due to the different densities of the gas and liquid phases, they experience different centrifugal forces during rotation. Driven by the initial tangential velocity, the gas-liquid mixture rotates within the chamber. The gas phase, with its lower density, experiences less centrifugal force and moves towards the center of the cyclone internals, concentrating near the axis of rotation. The liquid phase, with its higher density, experiences greater centrifugal force. The force can be tens to hundreds of times that of a gas. Under the action of centrifugal force, the micron-sized bubbles in the mixture aggregate and separate from the liquid phase, and then move towards the outer edge wall of the gas-liquid vortex internal component. Under the action of gravity, the liquid phase that has accumulated on the outer edge wall flows downward along the side wall and finally flows out at the outlet at the bottom of the gas-liquid vortex internal component. Under the action of buoyancy, the gas phase that has accumulated in the center of the gas-liquid vortex internal component moves upward and finally flows out from the overflow port at the top, thereby realizing the gas-liquid two-phase separation of hydrogen and electrolyte. The separated hydrogen gas phase component flows upward and is intercepted by the wire mesh demister located at the first gas phase outlet, and then discharged from the first gas phase outlet. S2: Throttling and Hydrogen Evolution and Secondary Separation: The liquid phase obtained from the primary separation enters the collection inlet pipe of the throttling device and is guided to the spiral guide cavity below. Under the closed-loop control of the flow sensor and pressure sensor, the rotating spiral valve core rotates dynamically according to the real-time operating conditions, changing the flow area of ​​the spiral channel. While the liquid phase is undergoing high-speed swirling motion in the spiral channel, it is sprayed out through the adjustable multi-hole nozzle. When the liquid passes through the throttling channel formed by the spiral valve core and the nozzle, the cross-sectional area of ​​the channel contracts sharply, resulting in a significant local pressure drop. This causes the internal pressure of the electrolyte to be lower than the saturation dissolution pressure of hydrogen, thereby causing the hydrogen dissolved in the electrolyte to be rapidly precipitated due to supersaturation. The precipitated hydrogen floats in the secondary separation cavity and is intercepted by the wire mesh demister located at the second gas phase outlet before being discharged from the second gas phase outlet. S3: Liquid phase recovery: The electrolyte after secondary separation is collected at the bottom of the separator and discharged from the liquid phase outlet, completing the gas-liquid separation process.

[0022] Furthermore, in step S1, the feed volume flow rate of the hydrogen-electrolyte mixture is 0.2–10 m³ / h, and the centrifugal acceleration generated after entering the gas-liquid cyclone internals is 10–30 g; within this centrifugal acceleration range, the micron-sized bubbles and electrolyte mist in the mixture fully aggregate and adhere to the inner wall under the action of centrifugal force, thereby achieving efficient separation of hydrogen from entrained liquid phase impurities.

[0023] Furthermore, the hydrogen-electrolyte mixture originates from the gas-liquid mixture generated in the electrolyzer during the water electrolysis hydrogen production process. The purified electrolyte discharged from the liquid phase outlet is returned to the electrolyte circulation pipeline of the water electrolysis hydrogen production system to reduce the re-entry of electrolyte carrying air bubbles into the electrolyzer, thereby inhibiting the accumulation of air bubbles on the electrode surface and maintaining the stable operation of the electrolysis process.

[0024] The present invention has the following beneficial effects: (1) The present invention adopts a two-stage progressive separation structure. The first stage separation achieves the rupture and coalescence separation of hydrogen microbubbles through centrifugal force, and the second stage separation achieves the release of dissolved hydrogen through pressure difference effect. The two work together to significantly improve the hydrogen separation efficiency and reduce the hydrogen content in oxygen to a low level.

[0025] (2) The present invention is equipped with a wire mesh demister before the gas phase outlet of the two-stage separation, which can effectively intercept the mist generated during the separation process, avoid the reduction of separation effect caused by mist entrainment, and improve the dryness of the discharged gas.

[0026] (3) By optimizing the parameters of components such as the gas-liquid cyclone internals, wire mesh demister, and throttling device, this invention further improves the separation stability and adaptability of the device and expands its application range. (4) The present invention has a compact structure, reasonable layout of each component, high operational stability, and the pressure drop of the throttling device can be adjusted according to actual needs to adapt to different separation conditions.

[0027] (5) The separation method of the present invention has simple steps, convenient operation, low energy consumption, and the electrolyte discharged at the bottom can be recycled and reused, which reduces production costs and has good industrial application prospects.

[0028] (6) The present invention integrates the design to solve the problems of dispersed equipment and complex pipelines in traditional processes, greatly reducing the floor space, reducing equipment investment costs and pipeline leakage risks, and improving the rationality of system layout.

[0029] (7) The present invention can simultaneously achieve efficient capture of micron-sized bubbles and mist in a single device, as well as active precipitation and secondary separation of dissolved hydrogen, thereby reducing the path of hydrogen migration to the anode through the liquid carrier from the source, fundamentally reducing the hydrogen content in oxygen, and ensuring the inherent safety and operational reliability of large-scale water electrolysis hydrogen production system. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure in Example 1. Detailed Implementation

[0031] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. However, these embodiments are not intended to limit the present invention. Any similar structures and similar variations of the present invention should be included in the protection scope of the present invention. The commas in the present invention all indicate the relationship between and. The English letters in the present invention are case-sensitive.

[0032] Example 1 like Figure 1 As shown, this embodiment provides a device for reducing the hydrogen content in oxygen using multi-stage gas-liquid separation technology, including a separator 1. The inner cavity of the separator 1 is divided into a primary separation chamber 11 and a secondary separation chamber 12 from top to bottom. The primary separation chamber 11 and the secondary separation chamber 12 are connected. By adopting a hierarchical layout, two-stage gas-liquid separation can be completed in a single housing, effectively reducing the device volume and improving integration and space utilization.

[0033] The primary separation chamber 11 is equipped with a gas-liquid cyclone internal component 2. The strong centrifugal force field generated by the gas-liquid cyclone internal component 2 causes micron-sized bubbles in the hydrogen-electrolyte mixture to coalesce and separate, efficiently removing free microbubbles from the hydrogen-electrolyte mixture. By using centrifugal force to enhance the collision, coalescence, and floating of micron-sized bubbles, the primary separation efficiency of free hydrogen is greatly improved, reducing the load on the subsequent secondary depressurization and gas evolution.

[0034] A throttling device is installed between the primary separation chamber 11 and the secondary separation chamber 12. The hydrogen-rich electrolyte, after primary separation in the primary separation chamber 11, is depressurized via the throttling device. This sudden drop in static pressure causes the supersaturated dissolved hydrogen to actively precipitate out and complete separation in the secondary chamber, thereby reducing the hydrogen content in the oxygen. Through controllable throttling and pressure reduction, a pressure surge occurs in the electrolyte over a short distance, forcing the supersaturated dissolved hydrogen to precipitate out, fundamentally reducing the hydrogen content in the electrolyte, and thus significantly reducing the hydrogen content in the oxygen, improving system operational safety.

[0035] Preferably, the separator 1 has a cylindrical structure made of stainless steel or titanium alloy, with a smooth inner wall and no dead corners, making it suitable for long-term stable operation in high-purity, high-humidity hydrogen-oxygen environments. The cylindrical cavity facilitates smooth gas phase floating and stable liquid phase settling, while the smooth inner wall prevents electrolyte retention and impurity accumulation. It is suitable for long-term stable operation in high-purity, high-humidity hydrogen-oxygen environments and exhibits excellent corrosion resistance and fatigue resistance.

[0036] Preferably, the gas-liquid vortex internal component 2 has an inlet 21 on its side, an outlet 22 at its bottom, and an overflow port 23 at its top.

[0037] The separator 1 has a first gas phase outlet 13 at its top, which is connected to the primary separation chamber 11 and is used to discharge the free hydrogen gas removed in the primary separation. This allows for the timely discharge of the hydrogen gas separated in the primary separation chamber, preventing the hydrogen gas from redissolving in the primary separation chamber 11 or entering the downstream with the electrolyte. The separator 1 also has a liquid phase outlet 14 at its bottom, which is connected to the bottom collection area of ​​the secondary separation chamber 12 and is used to discharge the clean electrolyte after deep dehydrogenation. This enables the stable reflux of the low-hydrogen-content electrolyte, ensuring the purity and safety of the electrolyte circulation in the electrolysis system.

[0038] The separator 1 has a hydrogen-electrolyte mixture inlet 15 on its side wall, which is connected to the inlet on the side of the gas-liquid cyclone internal component 2; this ensures that the gas-liquid mixture enters the gas-liquid cyclone internal component 2 tangentially or axially, directly forming a stable cyclone field and improving the initial efficiency of the first-stage separation.

[0039] The separator 1 is also provided with a second gas phase outlet 16 on its side wall, and the second gas phase outlet 16 is connected to the secondary separation chamber 12.

[0040] Preferably, the first gas phase outlet 13 and the second gas phase outlet 16 are independently connected to external pipelines, so that the gas phase discharged from the first separation chamber 11 and the hydrogen gas precipitated from the second separation chamber 12 are isolated from each other during the discharge process, avoiding cross-mixing, cross-flow or backflow of gases in different pressure areas, ensuring that the two-stage separation is independent and does not interfere with each other, and improving separation stability and control accuracy.

[0041] The second gas phase outlet 16 is located in the upper middle part of the secondary separation chamber 12 to ensure that the discharged gas phase is far away from the liquid phase accumulation area, reduce electrolyte mist entrainment, reduce the amount of liquid carried at the gas phase outlet, and improve the purity of the gas phase.

[0042] Both the first gas phase outlet 13 and the second gas phase outlet 16 are equipped with wire mesh demisters 4. The wire mesh demisters 4 can be metal wire mesh demisters or corrugated wire mesh demisters, and can be made of materials such as stainless steel, titanium, and nickel alloy. The mesh size is 80 mesh, which can effectively remove droplets larger than 3-5μm, with a separation efficiency of up to 99% or more. This prevents electrolyte mist from being discharged with hydrogen and avoids media loss and pipeline contamination.

[0043] The gas-liquid cyclone internal component 2 is one of the following: cyclone tube type internal component, axial cyclone blade type internal component, corrugated cyclone plate type internal component, or spiral flow channel type internal component. It can be flexibly selected according to the working conditions, flow rate, pressure and separation accuracy. It has strong versatility and is suitable for various water electrolysis hydrogen production working conditions.

[0044] The throttling device includes a spiral guide throttling device 3, which includes a throttling device body 31, a liquid inlet pipe 32, and an adjustable multi-hole nozzle 33. The throttling device body 31 is provided with a spiral guide cavity 311, which is connected to the liquid inlet pipe 32 and forms a spiral flow channel 312 inside, which is used to generate swirling flow of fluid and achieve preliminary pressure reduction and throttling. The spiral flow channel can enhance fluid disturbance and pressure loss, achieve stable throttling and pressure reduction in a small space, and avoid local cavitation and flow field oscillation.

[0045] The collecting inlet pipe 32 has a symmetrical bifurcated structure. Symmetrical inlet ensures that the fluid enters the spiral guide cavity 311 evenly, reducing flow deviation and impact, and improving the stability and consistency of throttling regulation. The collecting inlet pipe is connected to the inner walls on both sides of the separator, and the collecting inlet pipe 32 is connected to the inlet end of the spiral guide cavity 311, collecting the fluid and guiding it into the spiral guide cavity 311. The spiral guide cavity 311 is equipped with a rotatable spiral valve core. By rotating the spiral valve core, the flow area of ​​the spiral flow channel is changed to adjust the throttling opening. The throttling pressure difference and flow rate can be continuously adjusted online according to the real-time operating conditions to achieve precise and stable pressure reduction control and adapt to the gas evolution requirements under different loads.

[0046] The adjustable multi-hole nozzle 33 is connected to the outlet end of the spiral guide cavity. The adjustable multi-hole nozzle 33 includes at least one nozzle with a replaceable orifice diameter, used to control the flow rate and throttling opening by changing the nozzle flow area. Through multi-stage throttling and orifice diameter matching, the effect of local pressure drop is further enhanced, allowing dissolved hydrogen to be released more fully. At the same time, different flow rates and pressure drop requirements can be adapted by changing the nozzle.

[0047] Preferably, the throttling device may be selected from any one of an adjustable throttling valve, a flow-limiting orifice plate, a venturi tube, a capillary tube, a porous medium throttling device, a fixed throttling valve, or a nozzle.

[0048] The hydrogen-electrolyte mixture inlet is equipped with a pressure sensor and a flow sensor to monitor the flow rate and pressure signal of the inlet fluid in real time. This provides data support for the automatic adjustment of the throttling device, facilitates closed-loop automatic control, and ensures stable, efficient, and continuous operation of the separation and gas evolution process.

[0049] Example 2 This embodiment provides a method for treating a hydrogen-electrolyte mixture from the cathode side of an alkaline water electrolyzer using the apparatus described in Embodiment 1 above. The method includes: S1: First-stage cyclone separation: A hydrogen-electrolyte mixture is introduced into the gas-liquid cyclone internals of the first-stage separation chamber at a volumetric flow rate of 2.5 m³ / h through the hydrogen-electrolyte mixture inlet. The hydrogen-electrolyte mixture enters the gas-liquid cyclone internals through an inlet on the side. Under centrifugal force, it generates a centrifugal acceleration of approximately 22 g, causing micron-sized bubbles to collide, coalesce, and separate from the liquid phase, completing the gas-liquid separation process within the cyclone chamber. Due to the different densities of the gas and liquid phases, they experience different centrifugal forces during rotation. Driven by the initial tangential velocity, the gas-liquid mixture rotates within the chamber. The gas phase, with its lower density, experiences a smaller centrifugal force and moves towards the center of the gas-liquid cyclone internals, concentrating near the axis of rotation. The liquid phase, with its higher density, experiences a larger centrifugal force, which can be tens to hundreds of times greater than that of the gas. Under the action of centrifugal force, the mixture... Micron-sized bubbles in the electrolyte aggregate and separate from the liquid phase, then move towards the outer edge of the gas-liquid vortex internal component. Under the influence of gravity, the liquid phase aggregated on the outer edge flows downward along the side wall in a swirling motion, eventually flowing out at the outlet at the bottom of the gas-liquid vortex internal component. Under the influence of buoyancy, the gas phase aggregated at the center of the gas-liquid vortex internal component moves upward and eventually flows out from the overflow port at the top, thus achieving the gas-liquid two-phase separation of hydrogen and electrolyte. The separated hydrogen gas phase component flows upward, and after being intercepted by the wire mesh demister located at the first gas phase outlet, the entrained mist is discharged from the first gas phase outlet. S2: Throttling and Hydrogen Evolution and Secondary Separation: The liquid phase obtained from the primary separation enters the collection inlet pipe of the throttling device and is guided to the spiral guide cavity below. Under the closed-loop control of the flow sensor and pressure sensor, the rotating spiral valve core rotates dynamically according to the real-time operating conditions, changing the flow area of ​​the spiral channel. While the liquid phase is undergoing high-speed swirling motion in the spiral channel, it is sprayed out through the adjustable multi-hole nozzle. When the liquid passes through the throttling channel formed by the spiral valve core and the nozzle, the cross-sectional area of ​​the channel contracts sharply, resulting in a significant local pressure drop that keeps the pressure drop at 0.3 MPa. This makes the internal pressure of the electrolyte lower than the saturation dissolution pressure of hydrogen. Under this pressure drop, the hydrogen dissolved in the electrolyte is rapidly precipitated due to supersaturation. The precipitated hydrogen floats in the secondary separation cavity and is intercepted by the wire mesh demister at the second gas phase outlet before being discharged from the second gas phase outlet. S3: Liquid Phase Recovery: The electrolyte after secondary separation collects at the bottom of the separator and is discharged from the liquid phase outlet, flowing back to the electrolyte circulation pipeline of the water electrolysis hydrogen production system. After 72 hours of continuous operation, monitoring revealed no obvious bubble accumulation on the electrode surface, indicating a significant improvement in system operational stability.

[0050] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

Claims

1. A device for reducing the hydrogen content in oxygen using multi-stage gas-liquid separation technology, characterized in that, The separator includes a separator whose inner cavity is divided into a primary separation chamber and a secondary separation chamber from top to bottom, and the primary separation chamber and the secondary separation chamber are connected. The primary separation chamber is equipped with a gas-liquid cyclone internal component. The strong centrifugal force field generated by the gas-liquid cyclone internal component causes the micron-sized bubbles in the hydrogen-electrolyte mixture to coalesce and separate, efficiently removing free microbubbles from the hydrogen-electrolyte mixture. A throttling device is provided between the primary separation chamber and the secondary separation chamber. The hydrogen-rich electrolyte after primary separation in the primary separation chamber is depressurized by the throttling device. The sudden drop in static pressure causes the supersaturated dissolved hydrogen to actively precipitate out and be separated in the secondary chamber, thereby reducing the hydrogen content in the oxygen.

2. The device for reducing the hydrogen content in oxygen using multi-stage gas-liquid separation technology according to claim 1, characterized in that, The separator has a first gas phase outlet at the top, which is connected to the primary separation chamber, and a liquid phase outlet at the bottom, which is connected to the bottom collection area of ​​the secondary separation chamber. The separator has a hydrogen-electrolyte mixture inlet on its side wall, which is connected to the inlet on the side of the gas-liquid cyclone internal component. The separator is also provided with a second gas phase outlet on its side wall, which is connected to the secondary separation chamber.

3. The device for reducing the hydrogen content in oxygen using multi-stage gas-liquid separation technology according to claim 2, characterized in that, The second gas phase outlet is located in the upper middle part of the secondary separation chamber.

4. The device for reducing the hydrogen content in oxygen using multi-stage gas-liquid separation technology according to claim 2, characterized in that, Both the first gas phase outlet and the second gas phase outlet are equipped with wire mesh demisters on their inner walls.

5. The device for reducing the hydrogen content in oxygen using multi-stage gas-liquid separation technology according to claim 1, characterized in that, The gas-liquid swirling internal component is one of the following: swirling tube type internal component, axial swirling blade type internal component, corrugated swirling plate type internal component, or spiral flow channel type internal component.

6. The apparatus for reducing the hydrogen content in oxygen using multi-stage gas-liquid separation technology according to claim 1, characterized in that, The throttling device includes a spiral guide throttling device, which includes a throttling device body, a liquid inlet pipe, and an adjustable multi-hole nozzle. The throttling device body has a spiral guide cavity, which is connected to the liquid inlet pipe and forms a spiral flow channel inside, which is used to make the fluid swirl and achieve preliminary pressure reduction and throttling. The liquid collection inlet pipe has a symmetrical bifurcated structure. The liquid collection inlet pipe is connected to the inner walls of both sides of the separator. The liquid collection inlet pipe is connected to the inlet end of the spiral guide cavity, so as to collect the fluid and introduce it into the spiral guide cavity. The spiral guide cavity is equipped with a rotatable spiral valve core. By rotating the spiral valve core, the flow area of ​​the spiral flow channel is changed, thereby adjusting the throttling opening. The adjustable multi-hole nozzle is connected to the outlet end of the spiral guide cavity, and the adjustable multi-hole nozzle includes at least one nozzle with a replaceable orifice diameter.

7. The apparatus for reducing the hydrogen content in oxygen using multi-stage gas-liquid separation technology according to claim 2, characterized in that, A pressure sensor and a flow sensor are installed at the inlet of the hydrogen-electrolyte mixture.

8. A method for reducing the hydrogen content in oxygen using multi-stage gas-liquid separation technology, characterized in that, The method is applicable to the apparatus according to any one of claims 1-7, and the method includes: S1: First-stage cyclone separation: A hydrogen-electrolyte mixture is introduced into the gas-liquid cyclone internals of the first-stage separation chamber through the hydrogen-electrolyte mixture inlet. The hydrogen-electrolyte mixture enters the gas-liquid cyclone internals through the side inlet and completes the gas-liquid separation process within the cyclone chamber. Due to the different densities of the gas and liquid phases, they experience different centrifugal forces during rotation. Driven by the initial tangential velocity, the gas-liquid mixture rotates within the chamber. The gas phase, with its lower density, experiences less centrifugal force and moves towards the center of the cyclone internals, concentrating near the axis of rotation. The liquid phase, with its higher density, experiences greater centrifugal force. The force can be tens to hundreds of times that of a gas. Under the action of centrifugal force, the micron-sized bubbles in the mixture aggregate and separate from the liquid phase, and then move towards the outer edge wall of the gas-liquid vortex internal component. Under the action of gravity, the liquid phase that has accumulated on the outer edge wall flows downward along the side wall and finally flows out at the outlet at the bottom of the gas-liquid vortex internal component. Under the action of buoyancy, the gas phase that has accumulated in the center of the gas-liquid vortex internal component moves upward and finally flows out from the overflow port at the top, thereby realizing the gas-liquid two-phase separation of hydrogen and electrolyte. The separated hydrogen gas phase component flows upward and is intercepted by the wire mesh demister located at the first gas phase outlet, and then discharged from the first gas phase outlet. S2: Throttling and Hydrogen Evolution and Secondary Separation: The liquid phase obtained from the primary separation enters the collection inlet pipe of the throttling device and is guided to the spiral guide cavity below. Under the closed-loop control of the flow sensor and pressure sensor, the rotating spiral valve core rotates dynamically according to the real-time operating conditions, changing the flow area of ​​the spiral channel. While the liquid phase is undergoing high-speed swirling motion in the spiral channel, it is sprayed out through the adjustable multi-hole nozzle. When the liquid passes through the throttling channel formed by the spiral valve core and the nozzle, the cross-sectional area of ​​the channel contracts sharply, resulting in a significant local pressure drop. This causes the internal pressure of the electrolyte to be lower than the saturation dissolution pressure of hydrogen, thereby causing the hydrogen dissolved in the electrolyte to be rapidly precipitated due to supersaturation. The precipitated hydrogen floats in the secondary separation cavity and is intercepted by the wire mesh demister located at the second gas phase outlet before being discharged from the second gas phase outlet. S3: Liquid phase recovery: The electrolyte after secondary separation is collected at the bottom of the separator and discharged from the liquid phase outlet, completing the gas-liquid separation process.

9. A method for reducing the hydrogen content in oxygen using multi-stage gas-liquid separation technology according to claim 8, characterized in that, In step S1, the feed volumetric flow rate of the hydrogen-electrolyte mixture is 0.2–10 m³ / h, and the centrifugal acceleration generated after entering the gas-liquid cyclone internals is 10–30 g.

10. A method for reducing the hydrogen content in oxygen using multi-stage gas-liquid separation technology according to claim 8, characterized in that, The hydrogen-electrolyte mixture originates from the gas-liquid mixture generated in the electrolyzer during the water electrolysis hydrogen production process. The purified electrolyte discharged from the liquid phase outlet is returned to the electrolyte circulation pipeline of the water electrolysis hydrogen production system.

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